112 The Alligator and Its Allies 



inserted on the proximal end of the first phalanx 

 of the fifth finger. 



Aletacarpo-phalangeus I. digiti V. (Adductor 

 digiti minimi). Springs from the metacarpal bones 

 of the second and third fingers and is inserted on the 

 radial side of the first phalanx of the fifth finger. 



The Abdominal Muscles 



Obliqiius Abdominis Externiis (Grand oblique, 

 Aeusserer schiefer Bauchmuskel, Obliquus exter- 

 nus, Obliquus externus +internus + Serrati, Oblique 

 descendens). Springs, with a flat prong, from the 

 uncinate processes of the true ribs, thence it 

 extends as a tendinous aponeurosis, near the 

 lateral boundary of the ileo-costalis muscle, caudal- 

 ward to the region of the twenty-third (crocodile) 

 vertebra. From this fairly straight line of origin 

 the muscle takes a sharply distoventral course and 

 is inserted, at least in part, on the outer surface of 

 the sternal part of the ribs of the tenth to sixteenth 

 vertebras, but does not reach the mid- ventral line. 

 Under this chief part of the outer layer of the 

 abdominal muscle lies a second, more band-like 

 muscle mass which is also strong but of consider- 

 ably less extent. It takes its origin from the 

 outer surface of the middle third of the ribs. In 

 the region of the twentieth vertebra it fuses with 

 the upper layer, but inwardly reaches nearer the 

 median line than the upper layer. 



